Currently, Wireless Fidelity (WiFi) networks are widely applied, and currently, lots of communications devices. For example, communications devices such as a mobile phone, a computer, and a tablet computer, all support a WiFi technology. That is, these communications devices can perform network communication using a WiFi network. In addition, currently, WiFi networks are spread all over public places or private places. For example, a hotel, a school, a hospital, a house, and other places. When performing communication using a WiFi network, communications devices all perform communication using a frame in the WiFi network. That is. For information transfer between the communications devices, information is borne on the frame in the WiFi network, and then the information transfer is completed using the frame in the WiFi network. Information query means that a device (for example, a device A) intends to learn whether information matching a demand of the device exists in the surroundings. If a device (for example, a device B) that has information matching the demand exists in the surroundings, the device B may notify the device A that the device B has the matching information. For a WiFi network, in a query process, the two devices may interact using a WiFi frame.
Currently, the structure of a frame in a WiFi network is defined in an excessively complex manner, and in some cases, there is too much redundant information in the frame in the WiFi network. For example, a frame header in the structure of a probe request frame or a probe response frame includes a frame control field (Frame Control), a duration/identifier field (Duration/ID), an address field (Address), a sequence control field (Sequence), and the like, and the frame header occupies 28 bytes. If there is a little content to be queried for, the probe request frame and the probe response frame carry a little information, which may be one or more names or addresses. In these cases, a frame body may possibly occupy only several bytes and the frame body is a part that carries information. That is. For such a probe request frame or probe response frame, only several bytes are used for carrying information, and the other bytes may be understood as redundant information. As a result, there is much redundancy in a frame for transmission, and there is a little information that really matters, so that many network resources are occupied for query, leading to low utilization of the network resources.